1. Field of the Invention
The present invention relates to wipers and more particularly pertains to a windshield wiper having a heating element for melting ice formations on booth the wiper and an associated windshield.
2.Description of the Prior Art
The use of wipers is known in the prior art. More specifically, wipers heretofore devised and utilized for the purpose of cleaning glass surfaces are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
For example, a heated wiper blade is illustrated in U.S. Pat. No. 3,718,940 which comprises a blade for window wipers having an electrical resistance element extending therethrough for heating the wiping lip. The electrical resistance element is characterized by a thin membrane comprised of flat plate sections joined by flexible coupling sections adapted to be independently bendable within the wiper blade body without distortion thereof. The membrane is provided with maximum heat transfer and reinforcing features as related to the wiper blade body for a most direct and effective heat transfer to the working surface that is to be defrosted and wiped clean.
An electrically heated wiper blade utilizing a fibrous carbon heating element is described in U.S. Pat. No. 4,928,344 which may be incorporated into existing windshield wiper assemblies. The unit comprises an elastic wiper blade, and a flexible, fibrous carbon heating element disposed in the blade substantially along its entire length thereof. The heating element contains a plurality of fibrous carbon strands coaxially surrounded by a heat shrunk polymeric tube. The heating element is substantially flexible and allows the wiper blade to conform to the curves of the subjacent windshield.
Another patent of interest is U.S. Pat. No. 3,936,901 which discloses a wiper blade with an embedded heating element. The heating arrangement includes a resistance element encased in the blade element for heating water fed into the cavity and out of holes in the blade element onto an associated windshield. The resistance element is advantageously a wire arranged in a folded non-conductive tubular member encased in the blade element. The water dispensing holes dispense the heated water on both sides of the wiping element.
Other known prior art wipers include U.S. Pat. Nos. 4,967,437, and 4,928,345.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a windshield wiper having a heating element for melting ice formations which includes an elongated cylindrical body having a hollow interior and three wiping surfaces which project from the body and extend longitudinally along the wiper with a helical heating element concentrically positioned within the hollow interior of the wiper. Furthermore, none of the known prior art wipers teach or suggest a heated windshield wiper which comprises the aforementioned structure and which further comprises a fluid dispensing arrangement for dispensing fluid over the heating coil and through apertures in the wiping surface, as well as in air expansion assembly for expanding the cylindrical body and the wiping surfaces to fracture ice formations surrounding the wiper.
In these respects, the heated windshield wiper according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of cleaning an associated windshield while simultaneously melting ice formations on both the wiper and the windshield.